JANUARY 25, 2014

Three 2014 cars on track on Friday

One of them can even be heard, after Mercedes released audio of Nico Rosberg speeding past at the wheel of the unlaunched W05 for a 'filming day' at Silverstone.

The audio can be heard at http://www.youtube.com/watch?v=FkMh_PCfWTo

Also running at Silverstone was the locally-based Force India's VJM07, with Nico Hulkenberg at the wheel, while both of Toro Rosso's drivers were running in the newly Renault-powered STR9 at Misano in Italy.

Audio clips of the V6 engines on test benches had raised alarm bells among some F1 fans, but the new Mercedes clip - where the turbo whistle could be easily heard - was warmly welcomed.

"You guys had scared me with the sound of that engine test you posted last year," one commenter wrote, "but once in the track it sounds wonderful."